Question

In case of Protein-ligand docking, ______ ligands are often _____ in adapting their shape to fit the receptor binding pocket.

(a) small molecule, highly flexible

(b) large molecule, highly flexible

(c) large molecule, more flexible

(d) small molecule, less flexible

This question was posed to me during an online interview.

My doubt is from Conformational Flexibility in section Predicting the Structure of Protein – Biomolecular Interactions of Bioinformatics

Answer 1

Correct option is (a) small molecule, highly flexible

Easy explanation: The degree of conformational flexibility of a small molecule ligand (substrate, cofactor or inhibitor) can be considerable particularly where there are multiple torsion angles. This presents a major challenge in protein-ligand docking and several different approaches have been used to solve this problem.